Tank



July 11, 1944. i w. J. BIGLEY. JR 2,353,122

TANK

Original Filed Deo, 5l, 1941 v Sito'. 4%

Patented July 11, 1944 l' UNITED I Y Wiuiemrigiey,Jr.,-Weei1ewken,1N. J.originalY applicati@ December'v s1, V1941, serial No. 425,216.V Dividedand this; application i Maren 1o, 1943serie1No. 478,730'

solaires; (o1. sos- 10) v This application is a division of my copendingapplication, Serial No. 425,216, led December 371, 1941, forimprovementsin a tank. l

The invention of the vpresent application relates to new and improved`tank or tractor structures, vand more particularly,l.t`o improvementsVinfthe tracks therefor. Y' 'A A primary object of the invention is toprovide track constructions that will have longer lives and betterwearing properties than corresponding devices of the prior art. w

Another object of paramount'importance is to provide a track capable ofoperationat extremely high-speeds, without any danger of break down ordamage tothe structure or to the occupants f the vehicle. Tanks equippedwith devices of the present invention have been operated satisfactorily,during tests `under extremely adverse conditions, at speeds well inexcess of sixty miles per hour.

A further object of the invention is `to provide novel guiding meansassociated with the track and sprocket, to prevent the track frombecoming dislodged or accidentally removedfrom itsnormal, v trainedrelationabout the sprocket wheel and other wheels of the vehicle.

Still another object of the inventionis lto provide novel connectingmeans for the articulated links of the track and to provide improvedmeans for preventing removal of the connecting means. To this end, theinvention'provides means for positively preventing removal of the tracksection connecting pins, even though vthe'latter become brokenintermediate their ends, yet permitting ready removal and 'replacement'of the pins by an operator whenever desired, using simple, standardtools. Y.

Other and further objects andadvanta'gesfof the invention will beapparent to those skilled in the art, from a considerationofthefollowing description-ofcertain specic embodiments of theinvention, shown in the accompanying drawing,

in which: v Y

Y Figure `1 is a somewhat diagrammatic side elevation vof at tank ofthetype-with which the present. invention may be used; .Figure 2 is anelevation of .apreferred form of sprocket wheel and articulated track; YY

Figure 3 is a plan view of the ground engaging surface of thetractorftrack;

-.Figure 4 is a similar fragmentary view, on an enlarged scale, withcertain parts shown in section; and: i

. Figure. 5 is a transverse section through pin securing means shown inFigure 4.

Although not confined to such luse,-the sprocket of` the presentinventionmay be employed, `as indicated at I0 in Figure 1, as thedriving .sprocket for. a tank II having an armoured body I2, a gunturret I3, a plurality of independently sprung the wheelsV I4, I5, I6,II andv aguiding sprocket I8, about whichhthe track 20 is trained.Thefwheels `I4 I1 are preferably provided with pairs of solid rubbertires,l spaced apart to provide an annular guiding channel for thereception of fins associatedwith the track, as hereinafter explained.Thse wheels are preferably journalled Von stub axles 2I carried byindependently mounted bell crank levers 22 connected to links 23 havingtheir ends connected to heavy coil springs housed in cylinders 25.mounted on the side walls of the tankbetween the inner wall thereof andan outer armoured skirt 29. Since the structures and arrangements ofthese parts are not'claimed in this application, they are not shown indetail in the accompanying drawing and need not be described further. i

Referring to Figure 2, the driving sprocket ID comprises a hub 30 havinga'splined inner peripher`y`(not shown) adapted to be mounted upon acorrespondingly splined portion of the main drive shaft 32 ofV thevehicle. Spokes 33 radiate from the hub 30 and are connected, preferablyintegrally, at their ,outer "ends to a circumferentially slotted rimcomprising twoV annular members 34, as is more clearly ,shown in myparent application, identified above. .l Y The rim on both sides of theslot is vshaped to provide relatively narrow cylindrical surfaces 31 andradially inwardly and laterally inclined surfaces 39, similar totruncated cones and extending from the central circumferential area tothe side edge faces Vof the rim. Preferably, the inclination of the4surfaces 39 is substantially 45 from a plane normal to the wheelaxis.These inclined surfaces are of importance, in preventing stones or otherforeign bodies from becoming jammed between the sprocket and theadjacent faces of the track sections, as explained below.v

The sprocket Wheel also comprises a plurality o f wings 4,2 projectingradially outwardly from the inclined surfaces 39 in circumferentiallyspaced relation, with their outer edges disposed-in alignment with thecentral circumferential portions 3'I or, in other words, substantiallyon an axial -projection of the radially outermost ,edges of the inclinedsurfaces 39. Also, the wingsl 42 are preferably inclined rearwardly withrespect tothe normal direction of rotation of the sprocket and aredisposed in equal angular relation to a Vcentral planenormal to thewheel axis. Y

These wings perform an important dual function,'in that they providelateral support for certainof the track links, as hereinafter explained,and actas chopping blades to dislodge dirt, mud, stones or other foreignbodies that tend'to collect onthe adjacent surface of the track links.

The wings 42, 43. preferably comprise triangular elements which may beintegral with the rim. or

secured thereto as by welding. The spokesv33 preferably have associatedtherewith, strengthening or stiffening ribs 33a, and are preferablyformed integrally with the rim and hub, to provide a sturdy,rigid,unitary structure.

The rim sections 34 further comprise a plurality of substantiallyradially projecting bosses 48, arranged in pairs on opposite sides ofthe central, circumferential slot and spaced circumferenti-ally aroundthe rim, between the pairs of wings 42. Each pair of bosses is aperturedfor the reception of a stub axle or pin 50, vupon which an anti-frictionroller 5| is journalled. Preferably, the bosses extend outwardly as at52 beyond the periphery of the rollers, but are narrower than therollers to expose the latter at Aareas adjacent the periphery of thesprocket.

As pointed out in the aforesaid parent application, it should be notedthat the slot between the two rim sections is laterally enlarged at thespaces between the pairs of outwardly projecting bosses 48, by bevellingthe inner walls of the rim sections in order to more readily receive theguiding fins on the track, as hereinafter explained.

Referring to Figures 25, the track of the present invention comprises aplurality ofinterconnected, articulated links arranged in a repeatingcycle consisting of transversely elongated full width sections 15 andpairs of relatively narrow spaced apart sections 18, 11, the lattersections leaving central apertures 18. The sections 15 are provided witha plurality of sets of relatively narrow, forwardly and rearwardlyprojecting apertured bosses 19, 19 on their correspondingfront and rearedges. tioned, relatively wide forwardly and rearwardly projectingapertured bosses 88, 8|. Each ofthe narrow intermediate sections 11, 16has a set of forwardly andrearwardly projecting bosses 82, 83, staggeredwith respect to the bosses on the sections 15 and disposed adjacentthereto in the spaces therebetween. The sections are interconnected byhinge pins 84 extending through the apertures in the respective bosses,as indicated in Figure 4. Preferably, Veach pin extends entirely acrossthe track and has its end faces disposed within the aperture 85 in theoutermost bosses 82-82, 83-83 carried by the narrow track sections 16,11. Each of the bores in these end bosses is provided with an annularenlargement f or groove 86, in which a circular or G-shaped expansiblespring clip 81 is disposed. The spring clips are held firmly in thegrooves 86 by their resilient expanding tendency and, in Figures 4 and5, the clips are shown in somewhat contracted position, so that theyconstantly exert an expanding force againstv the bottoms of the grooves.The clips are disposed in abutting relation to the end faces of the pins84, to prevent endwise movement'thereof. Hence, even if the pins shouldbe broken intermediate their ends, they would not be dislodged fromoperative position in the-bores, and they would still perform theirconnecting function and the endless track, as a whole, would not bebroken.

Each full Width track section 15 has formed on its upper or innersurface a longitudinally arranged upwardly projecting n 88, merging atits front and rear ends with the central bosses 80, 8|. The fins arepreferably generally triangular in outline, as shown in Figure2, andhaveedges 89, 90 aligned with and adapted. to engage the rollers 5|Vcarried by the sprocket, as the fins approach the sprocket periphery andenter the groove therein. The lateral enlargement of the Also, they havecentrally posi- Y opposite to the full width sections 15 and provideseats for those sections, as well as preventing lateral tipping thereof,as the track moves around with the sprocket.

The bosses 48, and the rollers 5| enter the apertures 18 and engagebosses 80, 8| in driving relation, the latter acting as bearing surfacesfor the rollers.

The track sections 15, 16, 11 are preferably cast or `forged from hard,nickel-chrome steel and thens 88 are preferably formed integrally withthe sections 15, by forging or casting. The pins 84 are madeof similarmaterial and, in actual practice, it has been demonstrated that, withthe construction shown herein, no lubrication ofthe parts is required,even for extended usage.

If vone or more links of the chain become damaged, it is an extremelysimple matter to replace the same by the removal of the necessary springclips 81 and by driving out the connecting pins 84. Thus, the springclips 81 have numerous advantages and perform unexpected functions whenemployed in the manner shown herein. First, they prevent endwise removalof the pins in the event that the pins become broken in use. Second,they are relatively inaccessible and are completely protected frommutilation or damage by the enclosing bosses in which they are housed.Third, they may be readily removed by the use of a simple tool in thehands of a mechanic or soldier, for replacement of a pin or tracksection. Finally, they may be replaced with equal facility, so thatrepairs to the track can be made in the field `with little or notrouble.

It must be understood that the invention is not limited to the specificdetails of construction shown in the accompanying drawing and describedabove, but covers all modifications coming within the scope of theappended claims and their equivalents.

I claim:

l. A tank or tractor track comprising a series of sections havingtransversely spaced apertured bosses ontheir end edges, the sectionsbeing assembled with the bosses on each section intermeshing with thoseon the adjacent sections and with the apertures in each set ofintermeshing bosses of adjacent sections in alignment, the apertures inthe end bosses of each set having circumferentially continuous groovesin their sidewalls, a pin extending through each set of alignedapertures, and an expansible spring elementA co'nfined in the grooves inthe outermost apertures of each set of bosses in abutting relation tothe ends of the pin,A to prevent endwise removal thereof. Y

2. A tank ork tractor track comprising a series of sections havingtransversely spaced apertured bosses on their end edges, the sectionsbeing assembled with the bosses on each section intermeshing with thoseon the adjacent sections and with the apertures in each set ofntermeshing bosses of adjacent sections in alignment, the laterallyoutermost bosses of each set having enlarged .recesses associated withtheir apertures, a pin extending through each set of aligned apertures,and an expansible spring clip confined in each of said yrecesses inabutting relation to the opposite ends of the associated pin, to preventendwise removal thereof.

3. In a tank or tractor track comprising aseries of articulated sectionseach having a plurality of apertured bosses on its end edges disposed inintermeshing, transversely aligned relation with the bosses on theadjacent sections and a hinge pin disposed in the apertures in thebosses and connecting each section to the next, the irnproved means forpreventing accidental removal of theipins, Which comprise acircumferentially continuous laterally enlarged recess in the aperturein each of the outermost bosses of each set of intermeshing bosses and asubstantially circular spring clip seated in each recessy and eachhaving a portion engageable with the adjacent end face of the hinge pin,to prevent endwise removal thereof through the aperture in either of theoutermost bosses of each set. Y v

4. In a tank or tractor track comprising a series of articulatedsections each having a plurality of connecting each section to the next,the improved means for preventing accidental removal of the pins, whichcomprise a laterally enlarged annular recess in the aperture in one ofthe outermost bosses of each set of intermeshing bosses and a G-shapedspring clip seated in each recess and having a portion engageable Withthe end face of the hinge pin, to prevent endwise removal thereofthrough the aperture in the last-mentioned boss.

5. A tractor track comprising a line of sections having a plurality ofintertting apertur-ed `bosses projecting forwardly and rearwardly fromltheir corresponding edges, a single pin extending through the aperturesin each set of intertting bosses with its end faces disposed Within theapertures in the outermost bosses at opposite sides of the track, theaperture in each of the last- 20 ferential groove formed therein, and aneXpanapertured bosses on its end edges disposed in f mentioned bosseshaving a continuous circumsible spring clip seated under spring pressurein each groove and having a portion engaging the end face of the pin, toprevent endwise removal thereof from the bosses. i

WILLIAM J. BIGLEY, Jn.

